High definition 3D televisions based on stereoscopic display have become a recent trend. An ideal stereoscopic display can make the viewer appreciate the real image. The current techniques of showing three-dimensional images can be divided into two categories. One requires wearing a viewing aid in the form of goggles that filter left or right images either by time-shuttering, color filtering or polarization filtering. The other is designed for the naked eyes. Both have their advantages and disadvantages.
U.S. Pat. No. 6,266,106 discloses liquid crystal for a right eye and liquid crystal for a left eye, which are not positioned in one plane, but are positioned at a 5° incline. Specifically, both liquid crystals are inclined so that they are closer to the viewer's face as they approach the side of the face from the middle of the forehead. The inclination of liquid crystal as described sets the preferential direction of the visual view of the liquid crystal to be horizontal leads in that the direction by which the high contrast of liquid crystal can be obtained is toward the 3D display. It diminishes a phenomenon like cross-talk and allows the viewer to view the appropriate stereoscopic image. Liquid crystal for the right eye and liquid crystal for the left eye have the same construction. The liquid crystals make contrast with each other and then they are mounted on a liquid crystal shutter glasses portion. This makes positioning each electrode in the center of the liquid crystal shutter glasses portion possible. The electric circuit in the center of the liquid crystal shutter glasses portion makes it easy to make electric contact between the circuit and the electrode.
Wearing a viewing aid can give a better three-dimensional effect and more vivid color, but prolonged use will increase the stress on the viewer's eyes and may lead to discomfort.
U.S. Pat. No. 6,795,250 discloses a lenticular lens array for creating a visual effect for an image viewed through the lenticular lens array comprises a multiple lenticules adjacent to each other. Each lenticule comprises a lenticular lens element on one side and a substantially flat surface on an opposite side. Each lenticular lens element has a vertex and a cross section comprising a portion of an elliptical shape. Alternatively, the cross section can comprise an approximated portion of an elliptical shape. The elliptical shape comprises a major axis substantially perpendicular to the substantially flat surface of each respective lenticular lens element. The vertex of each respective lenticular lens element lies substantially along the major axis of the elliptical shape.
The naked-eye 3D or auto-stereoscopic display will cause less discomfort, but the quality of stereoscopic image is poor and the viewing angle is limited.
Accordingly, a new multiple-view auto-stereoscopic display scheme is needed to produce a high-quality 3D image.